Impl Send & Sync for JoinHandle#52759
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r? @TimNN (rust_highfive has picked a reviewer for you, use r? to override) |
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@bors r+ |
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@bors rollup |
Mark-Simulacrum
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…dle, r=TimNN Impl Send & Sync for JoinHandle This is just a cosmetic change - it slightly relaxes and clarifies the public API without effectively promising any new guarantees. Currently we have [these auto trait implementations](https://doc.rust-lang.org/nightly/std/thread/struct.JoinHandle.html#synthetic-implementations): ```rust impl<T: Send> Send for JoinHandle<T> {} impl<T: Sync> Sync for JoinHandle<T> {} ``` Bound `T: Send` doesn't make much sense because `JoinHandle<T>` can be created only when `T: Send`. Note that [`JoinHandle::<T>::join`](https://doc.rust-lang.org/nightly/std/thread/struct.JoinHandle.html#method.join) doesn't require `T: Send` so why should the `Send` impl? And the `Sync` impl doesn't need `T: Sync` because `JoinHandle<T>` cannot even share `T` - it can only send it to the thread that calls `join`.
kennytm
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…dle, r=TimNN Impl Send & Sync for JoinHandle This is just a cosmetic change - it slightly relaxes and clarifies the public API without effectively promising any new guarantees. Currently we have [these auto trait implementations](https://doc.rust-lang.org/nightly/std/thread/struct.JoinHandle.html#synthetic-implementations): ```rust impl<T: Send> Send for JoinHandle<T> {} impl<T: Sync> Sync for JoinHandle<T> {} ``` Bound `T: Send` doesn't make much sense because `JoinHandle<T>` can be created only when `T: Send`. Note that [`JoinHandle::<T>::join`](https://doc.rust-lang.org/nightly/std/thread/struct.JoinHandle.html#method.join) doesn't require `T: Send` so why should the `Send` impl? And the `Sync` impl doesn't need `T: Sync` because `JoinHandle<T>` cannot even share `T` - it can only send it to the thread that calls `join`.
bors
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Rollup of 11 pull requests Successful merges: - #52702 (Suggest fix when encountering different mutability from impl to trait) - #52703 (Improve a few vectors - calculate capacity or build from iterators) - #52740 (Suggest underscore when using dashes in crate namet push fork) - #52759 (Impl Send & Sync for JoinHandle) - #52760 (rustc_metadata: test loading atoi instead of cos) - #52763 (Omit the vendor component in Fuchsia triple) - #52765 (Remove unused "-Zenable_nonzeroing_move_hints" flag) - #52769 (Incorporate a stray test) - #52777 (Fix doc comment for 'ptr::copy_to' method) - #52779 (revert accidental atty downgrade) - #52781 (Use a slice where a vector is not necessary) Failed merges: r? @ghost
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This is just a cosmetic change - it slightly relaxes and clarifies the public API without effectively promising any new guarantees.
Currently we have these auto trait implementations:
Bound
T: Senddoesn't make much sense becauseJoinHandle<T>can be created only whenT: Send. Note thatJoinHandle::<T>::joindoesn't requireT: Sendso why should theSendimpl?And the
Syncimpl doesn't needT: SyncbecauseJoinHandle<T>cannot even shareT- it can only send it to the thread that callsjoin.